A comparison of bowel preparations for flexible sigmoidoscopy: oral magnesium citrate combined with oral bisacodyl, one hypertonic phosphate enema, or two hypertonic phosphate enemas

doi:10.1016/S0002-9270(99)00364-0

The American Journal of Gastroenterology

Volume 94, Issue 8, August 1999, Pages 2122-2127

https://doi.org/10.1016/S0002-9270(99)00364-0 Get rights and content

Abstract

OBJECTIVE:

Magnesium citrate with hypertonic enemas or oral bisacodyl provides superior preparation quality for sigmoidoscopy over enemas alone. We compared three magnesium citrate sigmoidoscopy preparations in a randomized, single-blind, controlled trial.

METHODS:

Two hundred and ninety-one adults scheduled for routine sigmoidoscopy were randomly assigned to receive one of three preparations containing oral magnesium citrate (296 cc) taken the night before the procedure in combination with the following: 1) oral bisacodyl (10 mg), given with the magnesium citrate the night before the procedure; 2) one hypertonic phosphate enema 1 h before the procedure; or 3) two hypertonic phosphate enemas, given singly at 2 and 1 h before the procedure. Endoscopists rated preparation quality, procedure duration, and depth of endoscopic insertion. Patients assessed preparation comfort and overall satisfaction.

RESULTS:

Preparation quality was rated as excellent or good for 80.6% in the bisacodyl group, 88.7% in the one-enema group, and 85.1% in the two-enema group (p = 0.30). Patients reported the oral bisacodyl regimen was better tolerated (p = 0.032). Although the three regimens were comparable in most side effects, the bisacodyl preparation was associated with more diarrhea (p = 0.0003). Mean procedure duration, mean insertion depth, and prevalence of diverticula and polyps were similar in all groups. Fewer than 4% of patients required repeat procedures due to poor preparation quality.

CONCLUSIONS:

There was no statistical difference between the quality of the three bowel preparations. Patients considered an oral bisacodyl and magnesium citrate regimen more easily tolerated, though it was associated with more diarrhea.

Introduction

Flexible sigmoidoscopy is among the most common outpatient procedures performed by primary care physicians (1). Good visualization of the colonic mucosa is essential to an adequate procedure. Numerous bowel preparations have been used over the years. Previous studies had not identified a clearly superior method and several found no significant difference between one- or two-enema preparations 2, 3, 4, 5, 6, 7. However, two studies published over the past 2 years have shown better preparation methods.

One study showed a significant improvement in preparation quality and patient comfort using a combination of oral magnesium citrate and oral bisacodyl over a hypertonic phosphate two-enema preparation (8). Another study recently published from several of our authors compared magnesium citrate plus two hypertonic phosphate enemas, versus one- and two-enema preparations (9). It also showed a significant quality improvement with the two-enema/magnesium citrate preparation over the enemas alone, with no difference seen between one- or two-enema preparations. There was no significant difference in patient comfort ratings between the groups.

Based on these studies, we surmised that the addition of oral magnesium citrate to either an oral cathartic agent or enemas improved bowel preparation quality. The remaining question we attempted to answer is whether enemas, either one or two, combined with magnesium citrate, are superior to a completely oral preparation of magnesium citrate and oral bisacodyl.

Section snippets

Materials and methods

All patients undergoing flexible sigmoidoscopy in the Madigan Army Medical Center (MAMC) Adult Primary Care Clinic between July 1, 1997 and July 10, 1998 and in the Walter Reed Army Medical Center (WRAMC) Gastroenterology Clinic between May 1, 1998 and August 7, 1998 were invited to participate. Exclusion criteria included undergoing the procedure without preparation, dementia, a history of serum creatinine >2.0 mg/dl, congestive heart failure, a history of hyperphosphatemia or hypermagnesemia,

Results

More than 95% of eligible patients enrolled and 89.3% of enrolled patients completed the study. Most of those patients not completing the study decided not to have the procedure, moved from the area, or had other medical testing supercede the procedure. Five patients violated blinding by identifying their preparation to the endoscopist (oral bisacodyl/citrate = 3, one-enema/citrate = 1, two-enema/citrate = 1). These patients were excluded from the preparation quality analysis. Study patients in

Discussion

Our study found no differences in preparation quality between an exclusively oral regimen (bisacodyl/citrate) and a combination of magnesium citrate with either one or two enemas. Patient satisfaction and tolerance of all three preparations was high, though patients clearly preferred the oral regimen to the enema regimens. There was a stepwise decrease in patient-reported preparation difficulty from the double-enema preparation, to the single-enema, and the exclusively oral regimen. This

Conclusions

In summary, clinicians performing flexible sigmoidoscopy should strongly consider the use of bowel preparations including magnesium citrate, in combination with either one hypertonic phosphate enema or oral bisocodyl. The use of these regimens would improve mucosal visualization, which would allow better polyp screening and reduce the number of repeat procedures due to poor preparations. The use of magnesium citrate and oral bisacodyl could also reduce nursing time. Such benefits could save

Acknowledgements

We thank Laurie Harrell, R.N. Without her assistance and dedicated vigilance as the protocol nurse, this study would not have been completed. We are indebted to her and cannot express our appreciation enough.

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Decreased efficacy of polyethylene glycol lavage solution (Golytely) in the preparation of diabetic patients for outpatient colonoscopy: A prospective and blinded study
2001, American Journal of Gastroenterology
Citation Excerpt :
Although diabetes mellitus is known to be associated with disturbances in bowel motility (11, 12), there are no studies specifically addressing whether patients with diabetes undergoing colonoscopy require a more vigorous colonic preparation than do those without diabetes. In a recent study comparing magnesium citrate versus phosphate enema bowel preparations for flexible sigmoidoscopy, however, diabetic patients were less likely to have preparations rated as excellent or good (13). The present study was designed to compare, in a prospective and blinded fashion, the efficacy of a standard outpatient Golytely preparation in diabetic versus nondiabetic patients.
OBJECTIVES:
The aim of the present study was to compare, in a prospective and blinded fashion, the efficacy of 6 L of polyethylene glycol–based lavage solution (Golytely) administered on an outpatient basis in diabetic versus nondiabetic patients.
METHODS:
A total of 54 consecutive nondiabetic and 45 consecutive diabetic patients requiring outpatient colonoscopy underwent colonic cleansing by drinking 6 L of Golytely the evening before the procedure. The entire procedure, from rectum to cecum, was videotaped and coded for later review by the Chief of Endoscopy who was blinded to the identity and medical history of the patients. The primary outcome measure was the quality of the preparation score, numerically rated on a 14-point scale (0–13) based on the surface area of the mucosa that could be examined and the consistency of the residual stool.
RESULTS:
There was a significant difference in the quality ratings for the bowel preparations, with an overall superior preparation in the nondiabetic group (2.4 ± 1.6 vs 5.4 ± 3.1, p < 0.001). A total of 97% of the nondiabetic patients had a preparation rated as good or better, compared with only 62% of the diabetic patients (p < 0.001). Preparations rated as poor or futile, necessitating repeat colonoscopy, occurred in no nondiabetic but in 9% of diabetic patients (p < 0.01). Within the diabetic group, there was no significant difference in bowel preparation scores between those patients aged >70 yr and those <70 yr, those requiring and those not requiring insulin, those with Hb A1c values >8% and those with values <8%, and those with and without peripheral neuropathy.
CONCLUSION:
We conclude that diabetic patients (irrespective of insulin use, diabetic control, or diabetic neuropathy) have a significantly poorer response to a 6-L Golytely preparation than do nondiabetic patients.
Resident participation in flexible sigmoidoscopy does not affect patient satisfaction
2000, American Journal of Gastroenterology
Citation Excerpt :
Because of the nonrandom nature of patient assignment to a resident, propensity score analysis was performed to assess the need to adjust for potential confounders (25, 26). These data were collected as part of two clinical trials comparing different bowel preparations for flexible sigmoidoscopy (27, 28). As there was no effect of the trial interventions on the outcomes reported in this study, confirmed in multivariate analyses, no adjustment for study wing was made.
OBJECTIVE:
We sought to assess the effect of resident involvement in flexible sigmoidoscopy on patient satisfaction and comfort.
METHODS:
Adults undergoing flexible sigmoidoscopy completed a previsit questionnaire on indication for procedure, GI-related history, and functional status. Immediately after the procedure, satisfaction and procedure comfort were assessed. Additional information collected included procedure duration, depth of sigmoidoscope penetration, and visualization of diverticuli or polyps.
RESULTS:
Among 408 endoscopies, patient characteristics and procedure indications were similar between sigmoidoscopies done by residents (n = 111) or staff. There were no differences in patient satisfaction, procedure comfort, or willingness to undergo the procedure again in the future. Sigmoidoscopies involving residents averaged 5.6 min longer, even after adjusting for preparation quality, depth of insertion, specific endoscopist, and the presence of polyps or diverticuli.
CONCLUSIONS:
Patient satisfaction and comfort with flexible sigmoidoscopy was not reduced by resident involvement, though the procedure duration was slightly longer.
Is whole-colon investigation by colonoscopy, computerized tomography colonography or barium enema necessary for all patients with colorectal cancer symptoms, and for which patients would flexible sigmoidoscopy suffice? A retrospective cohort study
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¹: The views expressed in this article are those of the authors and should not be construed to represent in any way those of the Department of Defense or the Department of the Army.

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Original ContributionsA comparison of bowel preparations for flexible sigmoidoscopy: oral magnesium citrate combined with oral bisacodyl, one hypertonic phosphate enema, or two hypertonic phosphate enemas1

Abstract

Introduction

Section snippets

Materials and methods

Results

Discussion

Conclusions

Acknowledgements

Gastrointest Endosc

Gastrointest Endosc

Am J Gastroenterol

Gastrointest Endosc

Gastrointest Endosc

Gastrointest Endosc

Patients, diagnosis, and procedures in a military internal medicine clinicComparison with civilian practices

Military Med

Comparison of three bowel preparations for sigmoidoscopy

WI Med J

Original Contributions
A comparison of bowel preparations for flexible sigmoidoscopy: oral magnesium citrate combined with oral bisacodyl, one hypertonic phosphate enema, or two hypertonic phosphate enemas1